Normalise mouse keycodes (#23975)

quantum/quantum_keycodes_legacy.h

@@ -16,3 +16,42 @@
 #define RGB_VAD QK_UNDERGLOW_VALUE_DOWN
 #define RGB_SPI QK_UNDERGLOW_SPEED_UP
 #define RGB_SPD QK_UNDERGLOW_SPEED_DOWN
+
+#define KC_MS_UP QK_MOUSE_CURSOR_UP
+#define KC_MS_U QK_MOUSE_CURSOR_UP
+#define KC_MS_DOWN QK_MOUSE_CURSOR_DOWN
+#define KC_MS_D QK_MOUSE_CURSOR_DOWN
+#define KC_MS_LEFT QK_MOUSE_CURSOR_LEFT
+#define KC_MS_L QK_MOUSE_CURSOR_LEFT
+#define KC_MS_RIGHT QK_MOUSE_CURSOR_RIGHT
+#define KC_MS_R QK_MOUSE_CURSOR_RIGHT
+#define KC_MS_BTN1 QK_MOUSE_BUTTON_1
+#define KC_BTN1 QK_MOUSE_BUTTON_1
+#define KC_MS_BTN2 QK_MOUSE_BUTTON_2
+#define KC_BTN2 QK_MOUSE_BUTTON_2
+#define KC_MS_BTN3 QK_MOUSE_BUTTON_3
+#define KC_BTN3 QK_MOUSE_BUTTON_3
+#define KC_MS_BTN4 QK_MOUSE_BUTTON_4
+#define KC_BTN4 QK_MOUSE_BUTTON_4
+#define KC_MS_BTN5 QK_MOUSE_BUTTON_5
+#define KC_BTN5 QK_MOUSE_BUTTON_5
+#define KC_MS_BTN6 QK_MOUSE_BUTTON_6
+#define KC_BTN6 QK_MOUSE_BUTTON_6
+#define KC_MS_BTN7 QK_MOUSE_BUTTON_7
+#define KC_BTN7 QK_MOUSE_BUTTON_7
+#define KC_MS_BTN8 QK_MOUSE_BUTTON_8
+#define KC_BTN8 QK_MOUSE_BUTTON_8
+#define KC_MS_WH_UP QK_MOUSE_WHEEL_UP
+#define KC_WH_U QK_MOUSE_WHEEL_UP
+#define KC_MS_WH_DOWN QK_MOUSE_WHEEL_DOWN
+#define KC_WH_D QK_MOUSE_WHEEL_DOWN
+#define KC_MS_WH_LEFT QK_MOUSE_WHEEL_LEFT
+#define KC_WH_L QK_MOUSE_WHEEL_LEFT
+#define KC_MS_WH_RIGHT QK_MOUSE_WHEEL_RIGHT
+#define KC_WH_R QK_MOUSE_WHEEL_RIGHT
+#define KC_MS_ACCEL0 QK_MOUSE_ACCELERATION_0
+#define KC_ACL0 QK_MOUSE_ACCELERATION_0
+#define KC_MS_ACCEL1 QK_MOUSE_ACCELERATION_1
+#define KC_ACL1 QK_MOUSE_ACCELERATION_1
+#define KC_MS_ACCEL2 QK_MOUSE_ACCELERATION_2
+#define KC_ACL2 QK_MOUSE_ACCELERATION_2